The chemistry-related aspects in the treatment of natural filamentary or fibrous materials to obtain filaments or fibres that are subsequently used for spinning, i.e. the recovery of the fibres and/or filaments from natural materials. It also covers the carbonisation of rags and other fibrous materials to recover animal fibres. Please note that in this context "carbonisation" does not mean that carbon fibres are produced, but only that vegetable impurities are removed from the fibres, usually by an aqueous acidic treatment.

Relationship between large subject matter areas

This subclass does not cover the treatment of fibrous materials after said materials have already been recovered from the natural materials, nor the treatment of fibrous materials after the filaments or fibres have been spun

The chemical treatment of natural filamentary or fibrous materials after the filament/fibres have been recovered from their natural matrices is classified in D06M, with the exception of the carbonisation of rags made of animal fibres. In case of doubt, both classes should be allocated.

When a document is also related to a neighbouring field it should always be circulated to the related classifiers. In the cases where many different applications of the invention are claimed, the document should only be circulated to the exemplified or the most relevant technical field.

The manufacture of artificial filaments or fibres is classified in D01D (mechanical aspects) and D01F (chemical aspects). Please note that man-made cellulosic fibres such as viscose or lyocell are considered to be artificial.

References relevant to classification in this group

This subclass/group does not cover:

Mechanical treatment of natural filamentary or fibrous materials to obtain filaments or fibres for spinning